The Virginia Beach Fire Department deployed two boats to help using side scan sonar equipment to locate debris or wreckage under water.

The coordinates of the images are handed over to the Coast Guard to investigate.

But as far as what those images could be, crews still aren't sure.

“Right now they're just targets under the water. They could be a log, they could be something floating, could be pieces of debris. It might not be anything at all substantial to the crash site," says Rob Darling with the Virginia Beach Fire Department.

Though the skies were clear and water calm, the frigid temps and now darkness make the search that much harder.

The Coast Guard is leading the rescue efforts. Two small boats were deployed as well as the Coast Guard Cutter Shearwater, which has the ability to stay out for up to five days if necessary.

About an hour after the helo went down, two Navy aircrews hoisted four crash victims from the water transporting them to Sentara Norfolk General.

Virginia Beach Fire has suspended its search for the night, but the Coast Guard says its crews will continue as long as they have to.